In recent years, mobile terminals such as a laptop personal computer and a mobile telephone terminal including a global positioning system (GPS) receiving function have become widespread. The mobile terminal allows a user (hereinafter referred to also as “operator”) to watch a desired stellar body, which is displayed by execution of a starry sky (stellar body) watching software that cooperates with various sensors such as a geomagnetic sensor and an acceleration sensor, only by pointing the mobile terminal toward a direction of a starry sky that the user wishes to watch. Such a mobile terminal can display a stellar body that could not be seen through a telescope with existence of a covering object such as a cloud or even below the horizon.
There are Patent Documents proposing a mobile terminal that displays a name of a corresponding constellation and an image of the constellation when the operator adjusts an orientation of the mobile terminal toward the direction of the constellation in concert with a GPS and a geomagnetic sensor and displays the direction of the corresponding constellation when the operator inputs the name of the constellation. This proposed mobile terminal allows the operator to enjoy an observation of the constellation even without knowledge relating to the constellation or information for identifying the constellation.
The following are related arts to the invention.
[Patent document 1] Japanese Patent Laid-Open Publication No. 2003-209598
[Patent document 2] Japanese Patent Laid-Open Publication No. 2004-13066
[Patent document 3] Japanese Patent Laid-Open Publication No. 2006-229549
[Patent document 4] WO 2002/021287